Here in Maryland, on the Chesapeake Bay in particular, the word "sook" has a very specific meaning, closely related to the meaning in agrarian U.S. dialect, i.e., a term of endearment or familiar name for a female bovine, a cow. In Chesapeake country, a sook is a female blue crab (Callinectes sapidus). Her male counterpart is called a jimmy.
--Tim Sayles, Annapolis